Slack adjuster



W. H. BASELT Nov. 5, 1935.

SLACK ADJUSTER Original Filed Dec. 13, 193D Ressuecl Nov. 5, 1935 PATENT OFFICE SLAC'K ADJUSTEE Walter B. Baselt, Chicago. Ill., assigner in Ametlcan Steel Foundries, Chicago, Ill., l corporation o! New Jersey original No. 1,947,444, dem February 2|,A `1934.

Serial No. 502,051, December 13, 1930.

Application for reissue June 18. 1934, Serial No.

The invention relates to brake rigging and has reference more particularly to a slack adjuster for taking up the slack in railway brake rigging.

Slack adjusters of the type with which the 5 present invention is principally concerned are generally manually operated screw mechanism for adiusting the connection between certain truck levers of the brake rigging, whereby the slack caused by the wear of the wheels and brake shoes and the wear and corresponding lengthening oi' the members of the brake rigging can be eliminated. To this end it is an object of the present invention to provide an improved slack adjuster of the above type employing relatively few parts, which will be efllcient in operation and will fulfill all requirements of service and manufacture.

An object of the present invention is to provide an improved slack adjuster having novel means to adjust the relative position oi the truck lever with which the same is associated, comprising a nut having integrally formed therewith housing means, thus eliminating the excessive number of parts heretofore employed in similar mechanisms.

With these and various other objects in view,

the invention may consist of certain novel features of construction and operation as will be more fully described and particularly pointed out in the specification, drawing and claims appended hereto.

In the drawing, which illustrates an embodiment of the device and wherein like reference characters are used to designate like parts- Flgure 1 is a plan view, parts being shown in section, of the slack adjuster constructed in accordance with the present invention;

Figure 2 is a side elevational view of the same:

Figure 3 is an end View of the device shown in l Figure 1; and

Figure 4 is a modified form of collar.

In the embodiment of the device selected for illustration in the drawing a tie rod IIJ is disclosed, having a frame comprising a slotted end providing spaced arms I2, which are joined at the end opposite the tie rod by a hub I4, 'Ihe iulcrum block Ii is adapted to have slidable movement upon the arms I2 and is provided with the centrally disposed socket IB. One of the truck levers of the brake rigging is adapted to have pivotal connection with the fulcrum block I6 and it is thus seen that movement of the block upon the arms I2 will function to vary the relative position of the truck lever with relation to the tie rod I0.

For eiiecting movement of the iulcrum block I6 5 Claims. (Cl. 18S-197) an elongated screw 20 is provided having an inwardly projecting end 22 ntting into the socket I8 formed in the fulcrum block, and by means of the pin 24 the block and the screw are pivotally secured together. Rotatably mounted within the g hub Il is a -nut 2l having a shoulder or an enlarged end 2l engaging the inner surface of the hub and being provided with an extension having a seating portion 21 and a plurality of dat surfaces 30 whereby the same may be easily gripped 10 by any suitable tool for imparting rotation to the nut. 'I'he nut 28 is provided with a centrally disposed bore having a. portion of the same threaded, as shown at 32, and the remaining portion located in the extension hollowed out to form 15 a cavity 3l of a diameter slightly larger than that of the screw 20. A groove 36 is formed upon the periphery of the nut 26 adjacent the enlarged end 28 and disposed in alignment with the groove is a duct or passage III in the hub I4, terminating 20 in an enlarged screw threaded aperture for accommodating the fitting l0. Since the nut 26 is adapted to have rotation within the hub Il 1ubrication of the surfaces can therefore be easily taken care o! by forcing'any suitable lubricant by 25 means of the alemite tting Ill through the passage 38 to the groove 26 where it will work its way between the surfaces of the members.

For preventing endwise movement of the nut 26 a collar 42 is suitably secured on the seating 30 portion 21 of the extension. the collar engaging the outside surface o1 the hub I4 and thus in connection with the enlarged end 28 serves to hold the nut in position in the hub Il against any tension exerted by the fulcrum block I6. 'Ihe col- 35 lar 42 may be shrunk on the seat 21 as in Figure l, or may take the form of the collar shown in Figure 4, wherein the same is split as at M to form spaced ends l5, the same being provided with the cut-away shoulders 46 for accommodat- 4g ing the rivet I8. With respect to nut 26 it will be noted that the extremity of the extension, that is, the portion provided with the fiat surfaces 3D, is of smaller diameter than the remainder of the nut. The structure makes for greater ease in 45 telescoping the collar over the extension when shrink iittng the same on the seating portion.

In operation oi' the slack adjuster the tie rod I0 may comprise any tie rod of the brake rigging having connection to the truck levers and con- 50 nection to the same in this case is eifected by plvotally joining the truck lever to the fulcrum block I6. Movement of the fulcrum block, therefore, upon the arms I2, will function to vary the relative position which the lever will assume in relation to the tie rod. For adjusting the position o! the lulcrum block it L, only necessary to cause rotation o! the rotatable nut 26 which will function to cause movement of the screw 20 through the threaded engagement the nut has with the screw. This movement oi the screw will thus impart corresponding movements to the fulcrum block to take up the necessary slack in the brake rigging. In order that the nut 26 may be readily turned when desired its projecting end or extension is provided with rlat surfaces 30 forming means whereby the same can be readily gripped by any suitable tool. 'I'he nut 26, in addition to having a threaded bore for cooperation with the threaded screw 2U, is provided with the extension having the cavity 3l which forms a housing for accommodating the projecting end of the screw. Since the nut 26, by reason of its construction, provides both a housing for the projecting end oi' the screw, as well as the operating means for the screw, it eliminates a number of parts heretofore employed in slack adjusters for periorrning these operations, and further has the advantage that the housing is integral with the body portion of the nut and therefore it is impossible for the parts to become loose.

It is to be understood that I do not wish to be limited by the exact embodiment of the device shown, which is merely by way of illustration and not limitation, as various and other forms of the device will of course be apparent to those skilled in the art without departing from the spirit of the invention or the scope oi the claims.

I claim:

1. In a brake slack adjuster, the combination oi a frame, a fulcrum block slidably mounted in the irame, a screw secured to the block and extending through an aperture in the frame, a nut rotatably mounted in said aperture and having threaded engagement with the screw, said nut having a hollow extension integral therewith for enclosing the end of the screw, and a collar secured to the exterior of the extension and engaging said trame for preventing longitudinal movement of the nut, the portion of the extension seating the collar being greater in diameter than the remainder o! the extension.

2. In a brake slack adjuster, the combination of a frame. a iulcrum block slidably mounted in the frame, a screw secured to the block and extending through an aperture in the frame to project beyond said frame, a nut rotatably mounted in said aperture and having threaded engagement with said screw, said nut being provided with a hollow extension integral therewith, said extension forming a housing for enclosing the projecting end of the screw and having a seating portion on the exterior thereof, and a collar mounted on said seating portion for preventing axial movement of the nut with respect to the frame, said 5 seating portion having the same diameter as that portion of the nut mounted in said aperture.

3. In a brake slack adjuster, a frame providing spaced arms joined at one end by a hub portion and connecting at their other end with brake rigging, a fulcrum block slidably mounted in the spaced arms, a screw secured to the block, an opening extending through the hub portion longitudinally of the spaced arms, a nut rotatably mounted for rotation in the opening and having l5 threaded engagement with said screw whereby rotation o! the nut causes longitudinal movement of the screw and fulcrum block connecting therewith, said screw extending beyond the frame and said nut having a hollow extension integral there- 20 with ior enclosing the projecting end of the screw,

a seating portion on theexterlor of said extension, said seating portion being a continuation of the nut and having the same diameter as the nut, and means preventing longitudinal movement of the nut including a flange integral therewith engaging one side of the hub portion and a shrunk collar on said seating portion engaging the other side of the hub portion.

4. In a brake slack adjuster, the combination of a frame, a fulcrurn block slidably mounted in the frame, a screw secured to the block and extending through an aperture in the frame, a nut rotatably mounted in said aperture and having threaded engagement with the screw, said nut having a hollow extension integral therewith and surrounding the side and end surfaces of the screw for completely enclosing the end of the screw, and a collar secured to the exterior of the extension and engaging said frame for preventing longitudinal movement of the nut.

5. In a brake slack adjuster, the combination of a jaw having a hub, a fulcrum block slidably mounted in said jaw, a nut rotatably mounted in said jaw, a screw secured to the block and in threaded engagement with said nut, said nut projecting through the hub of said jaw and being secured therein by a thrust shoulder engaging the inside of said hub and a shrink collar engaging the outside of said hub, said nut having a housing integral therewith for surrounding the side and end surfaces of the screw for completely enclosing the end of said screw.

WALTER H. BASELT. 

